1. Technical Field
This invention relates in general to motorcycles and in particularly to motorcycles having both foot clutch and foot brake systems. More particularly, it relates to a mechanical clutch and hydraulic brake systems for motorcycles.
2. Description of Related Art
In existing motorcycle clutch systems, a hand clutch lever is located on the handle bars and includes cable means for mechanically coupling the movement of the clutch to disengage and engage the clutch mechanism to allow shifting of the gears on those motorcycles having a mechanical shifted gear system. Other motorcycles with mechanical gear shifts employ one foot pedal for the clutch, again through cable arrangements for engaging and disengaging the hand shifted gears, while the other pedal is normally a brake pedal. In this arrangement, the throttle is controlled by hand on one side of the handle bar.
In an arrangement where one foot is used to engage and disengage the clutch and the other foot is used to engage and disengage the brake, constitutes somewhat of a hazard when a motorcycle is in stop and go traffic. In such situations, the motorcyclist would have to engage the clutch and shift the gear into neutral and then apply the brake and place the free foot on the ground to support the motorcycle. Also, the motorcyclists alternatively would engage the brake to slow down the motorcycle, then engage the clutch to shift into neutral and then fully apply the brake. With the motorcycle fully stopped, the motorcyclist would have to repeat the process in reverse, engage the clutch and shift into gear with the brake off and then accelerate.
Other arrangements have been provided by motorcycle manufacturer including automatic transmissions. In such arrangement, the transmission is controlled by a hand lever and the other hand operates the accelerator, such that only one foot is required for the brake with the other foot free to place on the ground. Still many motorcycle enthusiasts desire mechanical hand shifted transmissions where the usual arrangement is a foot pedal for the brake and a foot pedal for the clutch.
Moreover, many motorcycle manufacturers provide a hydraulic clutch system. Discussion of such a hydraulic clutch system is set out in U.S. Pat. No. 6,227,342 B1.
This invention sets forth a retrofit arrangement to provide a clutch/brake system, which allows a hand shift motorcycle rider the ability to routinely place a foot on the ground when coming to a complete stop and until take-off. This is accomplished by a single clutch/brake pedal, which may be located for the use of either the left foot or the right foot of the rider. Furthermore in three-wheel motorcycles, the combining of the clutch and brake operation by a single pedal would permit a handicap person having use of only one leg for various reasons to operate the three-wheel motorcycle in a completely safe manner.
The invention is accomplished by the movement of a foot lever through a cam arrangement to disengage the clutch and with further movement apply the brake while the clutch remains disengaged. This permits the motorcyclist to place one foot on the ground where it remains until the brake is released and the clutch engaged for taking off and accelerating the motorcycle.
Further, by adjusting the lag in the application of the brake after the clutch the brake may be partially applied before the clutch is disengaged. Such an arrangement would improve braking efficiency, the same as an automobile driver would apply the brakes before disengaging the clutch in a conventional stick shift mechanical gear box. In this arrangement the cam-brake linkage would initially apply the brake and upon further movement of the clutch/brake, the cam action would completely disengage the clutch. In starting after a stop, the gears would be shifted while the brake was applied and the clutch disengaged, then the clutch would be engaged just as the brake was released.